Thermoelectric conversion power generation is power generation for converting thermal energy into electric energy using a thermoelectromotive force (Seebeck effect) generated by giving a temperature difference in a thermoelectric conversion device.
The thermoelectric conversion device contains a p-type thermoelectric conversion material and an n-type thermoelectric conversion material, and the energy conversion efficiency of the thermoelectric conversion device depends on the figures of merit (Z) of the thermoelectric conversion materials. The figure of merit (Z) of each thermoelectric conversion material is calculated from the following formula (1) using the Seebeck coefficient (α), the electric conductivity (σ) and the thermal conductivity (κ) of the material; the larger the figures of merit (Z) of the thermoelectric conversion materials contained in the thermoelectric conversion device, the higher the energy conversion efficiency of the thermoelectric conversion device.Z=α2×σ/κ  (1)
In addition, as oxide thermoelectric conversion materials, a compound represented by the formula ACuO2+δ (A=Y, alkaline earth metal and rare earth metal) is known. See Oxide Thermoelectrics, 2002 (ISBN 81-7736-100-7), p. 213 to 234.
The figures of merit (Z) of the compound described in the reference are low, 10−12 to 10−10K−1, and a thermoelectric conversion material with a high figure of merit (Z) is required.